In the stack of equipment I tested this week are a TDS420A and 2246. I know I have enough, actually, more than enough, scopes. But, hey, I can probably buy either one for roughly 100USD, I know they both work, and, well, TEAS.

The TDS420A is pretty cool but the service manual doesn't appear to have schematics, so repair is of the swapping-boards sort. The 2246 is the low bandwidth sibling to the 2465 I have on my bench now. It does appear to be repairable, at least compared to the TDS420A.

*sigh* Typing that paragraph, I realize this is apple to bricks. And that I am leaning toward the TDS420A mostly because I don't have anything quite like it. After all, I don't need another oscilloscope, so I should buy the most interesting one. Nevermind.

Here's some "Tech Tips" for the TDS420 I stumbled across while looking it up to see what you're talking about. Not sure how relevant they are. Looks like the TDS420x were one of the last-last CROs they made before going all LCD; interesting juxtaposition of technologies there.

From experience, HP ones need a reasonable amount of force to make contact and they click and exert pressure on the pcb. The Commodore by comparison is silent, easy to press and nicely sprung and thus passes zero pressure onto the pcb.

The HP keyboard from the 35/45/34 era has a sheet of heat treated metal with little buckling springs formed into it; pressing the key causes the spring to "oilcan" and touch the contact on the board. The contacts are plated, and the contact force is pretty low; plus, as mentioned, the PCB is strongly reinforced. I don't have every single HP calculator style, but at least the ones with the metal sheet clicky keys are utterly reliable. I've never heard of someone having a flaky contact, especially due to issues with the PCB.

The HP sales people told us that if there was ever a key which had iffy contact behavior due to the spring, the solution was to hit the key really hard (presumably to stretch it out a little). I know a few people who tried that, even though they weren't really having contact issues (engineering students, ya know?). Again, never saw a problem. Maybe the newer HP keyboards were less sturdy, but I don't have anything newer than a 42s to use as comparison.

Here's some "Tech Tips" for the TDS420 I stumbled across while looking it up to see what you're talking about. Not sure how relevant they are. Looks like the TDS420x were one of the last-last CROs they made before going all LCD; interesting juxtaposition of technologies there.

Here's some "Tech Tips" for the TDS420 I stumbled across while looking it up to see what you're talking about. Not sure how relevant they are. Looks like the TDS420x were one of the last-last CROs they made before going all LCD; interesting juxtaposition of technologies there.

From experience, HP ones need a reasonable amount of force to make contact and they click and exert pressure on the pcb. The Commodore by comparison is silent, easy to press and nicely sprung and thus passes zero pressure onto the pcb.

The HP keyboard from the 35/45/34 era has a sheet of heat treated metal with little buckling springs formed into it; pressing the key causes the spring to "oilcan" and touch the contact on the board. The contacts are plated, and the contact force is pretty low; plus, as mentioned, the PCB is strongly reinforced. I don't have every single HP calculator style, but at least the ones with the metal sheet clicky keys are utterly reliable. I've never heard of someone having a flaky contact, especially due to issues with the PCB.

The HP sales people told us that if there was ever a key which had iffy contact behavior due to the spring, the solution was to hit the key really hard (presumably to stretch it out a little). I know a few people who tried that, even though they weren't really having contact issues (engineering students, ya know?). Again, never saw a problem. Maybe the newer HP keyboards were less sturdy, but I don't have anything newer than a 42s to use as comparison.

I wasn't implying that HP keyboards had that problem, it was just a suggestion for the reason why bd139 has gotten through so many calculators while I still have the ones I used at college in my teens and now I'm 70 and still using those same non HP calculators

In the stack of equipment I tested this week are a TDS420A and 2246. I know I have enough, actually, more than enough, scopes. But, hey, I can probably buy either one for roughly 100USD, I know they both work, and, well, TEAS.

The TDS420A is pretty cool but the service manual doesn't appear to have schematics, so repair is of the swapping-boards sort. The 2246 is the low bandwidth sibling to the 2465 I have on my bench now. It does appear to be repairable, at least compared to the TDS420A.

*sigh* Typing that paragraph, I realize this is apple to bricks. And that I am leaning toward the TDS420A mostly because I don't have anything quite like it. After all, I don't need another oscilloscope, so I should buy the most interesting one. Nevermind.

Now, a 53310A? I definitely need one of those. That I could use.

I would not recommend going for the TDS420. You don't get much for it except the TekProbe-interface. And Tek had a learning phase there: from the TDS-3xx (rotten) on to the mediocre 4xx's and then coming to grips with it.I have never worked with a 5xx, but as some SW solution seem to apply both to the 5xx and 6xx series they should be ok. I have a TDS-644 and that is where they make sense and fun.It is not a CRO but a raster display, as you can see from the VGA output. So there is no reason to be content with a monochrome one. Ok, it has 4 channels, but the aquisition performance is the same as the 2430. And when you follow the links on Tek-Wiki, you will read that the early 4xx FW versions were lacking some functions.And I would not go for the models which 'share' aquisition rate. Except the x8xs maybe, where overall performance is sufficient again when in 4 channel mode.

They are pleasant little things. I wouldn't get rid of mine, even though I don't use it much.

Maybe I ought to work on changing that.

Logged

There are lies, damned lies, statistics - and ADC/DAC specs.Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".Having fun doing more, with less

Yes it certainly looks nice. Comes with original manual this one as well by the looks and is well looked after. Hopefully insides will tell the same story.

Edit: I got through a few phases when buying HP kit. The i don’t need it phase. Then the I don’t have it phase. Then the I need it phase. Then the I want it to be delivered phase. Then the I’ve got it phase. Then the “will have to pry it from my cold dead hands” phase. 400E and 6284A are there already

Wow...power just took two giant dips but came back on, thankfully. Now a fire call for a transformer explosion about 3 miles away. On a different circuit than me but originate at the same substation. Also hearing reports of pole breaker trips and a tree down close to same area. Must have been one hell of short to almost take out the substation.

Update, Yea.....it's now chaos down in town. Power outages, traffic lights out, total cluster.

And now I've finally got a minute to post some pics... I went and did it just to prove I wasn't just blowing smoke up your arse.

As always... the fabricobbling comes easy; its documenting shit that makes it take 3 times as long.

Yup.

But that is sufficiently interesting and valuable to other people that it is worth giving it a proper title in a thread of its own. As it is, buried in message 29k of (probably) >50k, nobody will find it again.

Nah, bitseeker will add it to the POI's.

Not very likely to be found by google and the TekScopes mob.

Or add it to 2465B Teardown thread.

*Takes a bow and put on best Elvis grin and southern drawl* "Spank you! Spank you vurry mu-u-uch!!!"

Yeah, I know it'll make a good article... but right now it's just a collection of pictures. I want to get a chance to finish the project and show it installed, but I've been a bit busy this week with the 454 project, fixing musical instruments and being overrun with the little dragonlings.

I'll add it to the big 2465 thread when and if I get a chance to add some narrative.

mnemMy house looks like I'm losing at Jumanji.

I'm glad I inspired you to right a booty fab wrong but when you do the write up keep my name out of it.

Back from a week out west and having a day out as "Matt Dillon"... or at least per what "Miss Kitty" says (no photos I'm aware of thankfully).

I accomplished the mission objective of picking up the awesome $50 Pacific Measurements 1038-D14, H13 and x2 - V12's with a 12868 power detector that came from the NRAO VLA post BCCS and into the SCM. I also think there are signs of Bait Theory, NSA, POS and MIP (at least buying the cheaper items will give me the faith and courage to purchase the more expensive or if I find... signal generator) happening too and definitely HFO.

That adds to the 1038-D14 NS20 w/NS201 and 1038-D14A N10 systems I have with two 15273 detectors and an RJ21 Telco 50 cable plus some directional couplers I already had prior (you know... though need documentation regarding). Plus I have four more detectors on the way.

I also picked up some other items ($20 USB 3.0 Mobo desktop that I thought just for the heat sinks and case was worth it since is only a mobo with video card and case, a round bottom copper bowl, misc items for random projects from the goodwill stores) and a free Brother MFC9970CDW Color Laserjet that the engineering office lady said needs the fuser replaced and otherwise works great. Double side scans also so will come in handy too for scanning the above pile of PM/Wavetek manuals. A manual binder machine would be handy to unbind and rebind... hhhmmm...

Ordered a "WAVETEK 6000 INSTRUMENTATION COMPUTER NS20 APPLICATION SOFTWARE MANUAL" for the reference library for these systems. Would be nice if has the code.

If anyone has any documentation related to the N10, NS20 or NS201... I sure would like a copy. I just missed buying a N10 manual on eBay since sold before I received a reply from the seller who listed as "Wavetek 1499-15126 Network Analyzer Model 1038-N10 Operating + Maintenance".

Last night I also figured out that the ~$4 shopgoodwill.com Motorola ATRIX HD MB886 smart phone is super picky with USB cables and required USB Debug Mode enabled to allow for Mass Storage data transfer with "one" of the cables I have out of the four I tried. Still haven't figured out how to access the phone internal memory yet... though am able to transfer from the SD card. Drivers on the laptop I'm guessing is the issue. I picked that up for an upgrade from the LG Thrive LG-P506 since that still runs Android 2.2.1 and I want something that runs at least Android 4.0 for some mobile Audio and RF Spectrum Analysis capabilities testing.

*Takes a bow and put on best Elvis grin and southern drawl* "Spank you! Spank you vurry mu-u-uch!!!"

Yeah, I know it'll make a good article... but right now it's just a collection of pictures. I want to get a chance to finish the project and show it installed, but I've been a bit busy this week with the 454 project, fixing musical instruments and being overrun with the little dragonlings.

I'll add it to the big 2465 thread when and if I get a chance to add some narrative.

mnemMy house looks like I'm losing at Jumanji.

I'm glad I inspired you to right a booty fab wrong but when you do the write up keep my name out of it.

No. And I've already saved the picture of that booty fab, so you cannae deny it.

Yes it certainly looks nice. Comes with original manual this one as well by the looks and is well looked after. Hopefully insides will tell the same story.

Edit: I got through a few phases when buying HP kit. The i don’t need it phase. Then the I don’t have it phase. Then the I need it phase. Then the I want it to be delivered phase. Then the I’ve got it phase. Then the “will have to pry it from my cold dead hands” phase. 400E and 6284A are there already

*Takes a bow and put on best Elvis grin and southern drawl* "Spank you! Spank you vurry mu-u-uch!!!"

Yeah, I know it'll make a good article... but right now it's just a collection of pictures. I want to get a chance to finish the project and show it installed, but I've been a bit busy this week with the 454 project, fixing musical instruments and being overrun with the little dragonlings.

I'll add it to the big 2465 thread when and if I get a chance to add some narrative.

mnemMy house looks like I'm losing at Jumanji.

I'm glad I inspired you to right a booty fab wrong but when you do the write up keep my name out of it.

No. And I've already saved the picture of that booty fab, so you cannae deny it.

mnemYou will figure prominently in my memoirs.

Poor Med.

Twas great repair mnem and done in proper MacGyver fashion and well enough with the gear at hand to bring a tear to this tight Scotsmans eye. (happy tears)